If you often focus on currency circle news, you should have heard a word: 51% attack. The word in general and the “hacker”, “steal money”, “loss of millions of other words appear together.
Now there are more than one currency suffered 51% attacks, including a plurality of bits of gold, Verge bifurcation and MonaCoin currency bitcoin, and the father of bitcoin encryption currency has always been as steady as Mount Tai never worries about this risk, on their own.
Because the bitcoin an attack, really! Expensive！ The!
What is the 51% attack?
In fact, this concept has been for having heard it many times from literally, is the master of the more than 50% of the work force, has absolute control over a block chain. Once you have the right to control the equivalent of taking over the chain, can even change the core system known as the “can not be tampered with, they can:
1, reverse the transaction issued, it is double trading; Confirm 2, prevent other transactions; 3, to prevent other blocks out.
When the attacker has 40% force, after the 6 block is confirmed, the attack success rate is 50%. In the whole network is greater than 50% the attacker control force, the attack success rate will reach 100%.
So in general, in order to protect a block chain network from 51% attacks, you need to make a balance for a cost of the process, such as mining.
Mining why so expensive?
In addition to mining, the basic cost of mining equipment, and electricity and other expenses, such as maintenance costs of cooling facilities. The cost of electricity is considered the most factors of the miners.
In the mining process, bitcoin miners need high performance computer to create block. With the passage of time, the block to create more and more difficult, we need better performance of the computer, the power consumption also increases.
In some countries, bitcoin mining has spent a considerable proportion of local power. As in Australia, Holland and Czech, bitcoin mining cost of power is more than the local 10% in Czech, the proportion is nearly 45%.
Display encryption research company CoinShares recently released assets bitcoin mining report, a large number of bitcoin mine has left China, moved to Russia, Canada and the United States and other places, looking for cheap electricity, abundant power supply, regulatory policy friendly, Internet access quickly and the cold weather set up local mines.
In this case, the 51% attack to be successful in the bitcoin network, need more than 5 million sets of professional ASIC machine to do is force support, so the power consumption is expected to 29.3 kwh, equivalent to the annual electricity consumption in Morocco.
Plus about $250 million in infrastructure and maintenance costs, the whole attack process cost $1 billion 400 million, can be said to be extremely expensive.
The bitcoin what it means?
For every about 200000 bitcoin transactions, network security is very important. The ingenious combination of cryptography and mining incentives, making bitcoin bitcoin network which is as strong as iron, as a store of value and commercial potential value and attractiveness.
While the 51% attack bitcoin astronomical cost to add a layer of natural protective cover, any private entities are not likely to use this money to attack the bitcoin network.
Even in theory, is feasible, but such attacks will make the booty become worthless, even to negative returns”. Because bitcoin is as strong as iron attack, which itself is a kind of destruction of bitcoin consensus and trust mechanism, the currency will directly lead to lack of confidence, thus affecting the price and currency market.
This also lost the motivation to attack. If it is not true for revenge on society, destroy bitcoin, is generally not a “stupid thief” to do such a sacrifice.
Copycat coin will have frequently been 51% attacks?
Compared with bitcoin, other copycat coins are not so lucky. Since 2018 51%, the number of attacks in the surge in the first half of this year, Verge is three times the 51% attack, bitcoin gold and ZenCash have not been spared.
@ the daily planet recently published an article, estimated on several mainstream monetary policy implementation 1 hours 51% attacks need to spend much money,
1, attack bitcoin 1 hours: $280 thousand 2, attack Fang 1 hours: $90 thousand Ethernet 3, attack bitcoin cash 1 hours: $15 thousand 4, 1 hour attack Wright currency: $20 thousand
The mainstream of the currency market still has a certain attack cost, and like other copycat coins such as Traid, PACcoin and other tokens 1 hours of attack cost only US $5. Even more surprising is that the market there are still a large number of tokens such as Zetacoin, Bata, Cream, their 1 hour attack cost is zero!
This greatly increases the probability of currency copycat attack, such attack is likely to occur frequently in the future. At the same time, it also let the community fully realized the superiority of bitcoin.
In the field of cryptography rely on digital currency, bitcoin is the first mover advantage is very obvious. In early July 2013, bitcoin, the whole network is the world’s top 500 supercomputer is 20 times the force and has reached 51%, so the attack for bitcoin is not a big problem what.
Block chain although known as safe, but some small block chains are not what they claim to be difficult to break. At present, bitcoin is still on the market the most secure encryption of digital money, no one.